Table 1.
Unadjusted and adjusted* backward stepwise Cox regression models for vulnerabilities associated with HCV incidence among Cedar participants who used injection drugs (n = 148)
| Variable | Baseline^ n (%) | Unadjusted HR (95%CI) | P value | Adjusted HR (95%CI) | P value |
|---|---|---|---|---|---|
| Location |
|
|
|
- |
|
| Prince George |
63 (42.6) |
1.48 (0.82, 2.66) |
0.676 |
|
|
| Vancouver |
85 (57.4) |
1.0 (Reference) |
|
|
|
| Sex |
|
|
|
|
|
| Female |
79 (53.4) |
1.43 (0.79, 2.60) |
|
- |
|
| Male |
69 (46.6) |
1.0 (Reference) |
0.240 |
|
|
| Age at enrolment |
23.1** (3.9) |
0.95 (0.87, 1.02) |
0.161 |
- |
- |
| Sexual identity |
|
|
|
|
|
| Gay/bisexual/two-spirited |
17 (11.5) |
1.62 (0.72, 3.63) |
0.242 |
- |
- |
| Straight |
131 (88.5) |
1.0 (Reference) |
|
|
|
| At least one parent in residential school |
|
|
|
- |
- |
| Yes |
81 (54.7) |
0.95 (0.53, 1.70) |
0.850 |
|
|
| No/unsure |
67 (45.3) |
1.0 (Reference) |
|
|
|
| Ever taken into foster care |
|
|
|
- |
- |
| Yes |
101 (68.2) |
1.29 (0.67, 2.51) |
0.445 |
|
|
| No |
47 (31.8) |
1.0 (reference) |
|
|
|
| Ever sexually abused |
|
|
|
|
- |
| Yes |
76 (52.1) |
1.66 (0.91, 3.04) |
0.098 |
- |
|
| No/unsure |
70 (47.9) |
1.0 (reference) |
|
|
|
| Sexual assault last 6 months |
|
|
|
- |
- |
| Yes |
3 (2) |
1.19 (0.37, 3.85) |
0.770 |
|
|
| No |
145 (98) |
1.0 (reference) |
|
|
|
| Relationship status last 6 months |
|
|
|
- |
- |
| Single |
115 (77.8) |
0.96 (0.64, 1.45) |
0.856 |
|
|
| In a relationship |
33 (22.2) |
1.0 (Reference) |
|
|
|
| Ever on streets for >3 nights |
|
|
0.845 |
- |
- |
| Yes |
56 (38.1) |
0.94 (0.52, 1.72) |
|
|
|
| No |
91 (61.9) |
1.0 (reference) |
|
|
|
| On street for > nights last 6 months |
|
|
|
|
- |
| Yes |
n/a |
1.26 (0.83, 1.90) |
0.275 |
- |
|
| No |
|
1.0 (reference) |
|
|
|
| Ever been in jail prison |
|
|
|
|
|
| Yes |
97 (66) |
1.11 (0.59, 2.09) |
0.742 |
- |
- |
| No |
50 (34) |
1.0 (reference) |
|
|
|
| Been in jail or prison last 6 months |
|
|
|
- |
- |
| Yes |
38 (25.7) |
1.25 (0.83, 1.89) |
0.291 |
|
|
| No |
110 (74.3) |
1.0 (reference) |
|
|
|
| Ever attempted suicide |
|
|
|
|
|
| Yes |
66 (44.6) |
0.67 (0.37, 1.23) |
0.195 |
- |
- |
| No |
82 (55.4) |
1.0 (reference) |
|
|
|
| Number of lifetime sexual partners |
|
|
0.530 |
- |
- |
| >20 |
70 (48.6) |
1.21 (0.67, 2.18) |
|
|
|
| <20/refused |
74 (51.4) |
1.0 (reference) |
|
|
|
| Ever involved in sex work |
|
|
|
- |
- |
| Yes |
67 (45.6) |
1.63 (0.90, 2.96) |
0.107 |
|
|
| No |
80 (54.4) |
1.0 (reference) |
|
|
|
| Involved in sex work last 6 months |
|
|
|
|
|
| Yes |
47 (31.8) |
1.71 (1.16, 2.53) |
0.007 |
1.59 (1.05, 2.42) |
0.030 |
| No |
101 (68.2) |
1.0 (reference) |
|
1.0 (reference) |
|
| Condom use for insertive sex with regular partner last 6 months |
|
|
|
- |
- |
| Not always |
62 (41.9) |
0.82 (0.51, 1.34) |
0.437 |
|
|
| Always |
86 (58.1) |
1.0 (reference) |
|
|
|
| Condom use for insertive sex with causal partner last 6 months |
|
|
|
- |
- |
| Not always |
28 (18.9) |
0.60 (0.24, 1.48) |
0.268 |
|
|
| Always |
120 (81.1) |
1.0 (reference) |
|
|
|
| Condom use for insertive sex with clients last 6 months |
|
|
|
- |
- |
| Not always |
6 (4.1) |
1.96 (0.61, 6.36) |
0.260 |
|
|
| Always |
142 (95.9) |
1.0 (reference) |
|
|
|
| Ever had a STI |
|
|
|
|
|
| Yes |
65 (43.9) |
1.17 (0.65, 2.12) |
|
- |
- |
| No |
83 (56.1) |
1.0 (reference) |
0.604 |
|
|
| Had a STI last 6 months |
|
|
|
|
|
| Yes |
16 (10.8) |
0.94 (0.36, 2.50) |
0.908 |
- |
- |
| No |
132 (89.2) |
1.0 (reference) |
|
|
|
| Ever overdose |
|
|
|
|
|
| Yes |
48 (32.4) |
0.76 (0.42, 1.40) |
0.382 |
- |
- |
| No |
100 (67.6) |
1.0 (reference) |
|
|
|
| Overdose last 6 months |
|
|
|
|
|
| Yes |
20 (13.5) |
1.71 (0.82, 3.58) |
0.152 |
- |
- |
| No |
128 (86.5) |
1.0 (reference) |
|
|
|
| Time since initiation of injection drug use1 |
|
|
|
|
|
| < 2 years |
n/a |
4.57 (2.19, 9.51) |
<0.001 |
4.14 (1.91, 8.94) |
<0.001 |
| 2-5 years |
|
2.43 (1.09, 5.45) |
0.031 |
2.12 (0.94, 4.77) |
0.070 |
| > 5 years |
|
1.0 (reference) |
|
1.0 (reference) |
|
| Frequency of injection cocaine last 6 months |
|
|
|
|
|
| Daily |
16 (10.8) |
3.94 (2.49, 6.24) |
<0.001 |
2.47 (1.51, 4.05) |
<0.001 |
| < Daily/non-user |
132 (89.2) |
1.0 (reference) |
|
1.0 (reference) |
|
| Frequency of injection methamphetamine last 6 months |
|
|
|
- |
- |
| Daily |
4 (2.7) |
1.79 (0.90, 3.57) |
0.099 |
|
|
| < Daily/non-user |
144 (97.3) |
1.0 (reference) |
|
|
|
| Frequency of injection opiates last 6 months |
|
|
|
- |
- |
| Daily |
27 (18.2) |
2.06 (1.43, 2.98) |
<0.001 |
|
|
| < Daily/non-user |
125 (81.7) |
1.0 (reference) |
|
|
|
| Syringe sharing last 6 months |
|
|
|
|
|
| Yes |
19 (12.8) |
3.35 (2.09, 5.39) |
<0.001 |
2.56 (1.47, 4.49) |
0.001 |
| No |
129 (87.2) |
1.0 (reference) |
|
1.0 (reference) |
|
| Reuse of own syringes last 6 months |
|
|
|
- |
- |
| Yes |
13 (9.1) |
2.17 (1.48, 3.19) |
<0.001 |
|
|
| No |
131 (90.9) |
1.0 (reference) |
|
|
|
| Hard to find new syringes last 6 months |
|
|
|
- |
- |
| Yes |
15 (10.1) |
2.16 (1.31, 3.57) |
0.003 |
|
|
| No |
133 (89.9) |
1.0 (reference) |
|
|
|
| Need help injecting last 6 months |
|
|
|
- |
- |
| Yes |
38 (25.7) |
1.14 (0.61, 2.14) |
0.687 |
|
|
| No |
110 (74.3) |
1.0 (reference) |
|
|
|
| Accessed any alcohol or drug treatment program last 6 months |
|
|
|
- |
- |
| Yes |
31 (21.1) |
1.25 (0.81, 1.93) |
0.317 |
|
|
| No |
116 (78.9) |
1.0 (reference) |
|
|
|
| Unable to access drug treatment program |
|
|
|
- |
- |
| Yes |
22 (15) |
0.90 (0.48, 1.69) |
0.741 |
|
|
| No |
125 (85) |
1.0 (reference) |
|
|
|
| Currently in methadone treatment program |
|
|
|
- |
- |
| Yes |
5 (3.4) |
2.11 (0.83, 5.37) |
0.117 |
|
|
| No | 143 (96.6) | 1.0 (reference) |
*All variables significant at the p ≤ 0.10 level in unadjusted analysis were included in the adjusted backward stepwise Cox proportional hazards model.
HR Hazard Ratio.
^Responses with less than n = 148 participants reflect missing data.
**Mean age (standard deviation).
1For those who had seroconverted to HCV positive, variable was time to seroconversion; and those who were non-incident cases, variable measured time to last follow up visit since initiation of injection.
n/a: not available.